Rotary pump



G. B. PETSCHE.

ROTARY PUMP.-

APPLICATION FILED 001.6, 1920.

1380,0159 Patented y 31, 1921.

A TTORNE Y ens'rnv 18. reasons, or vorfxnns'nnw YORK.

ROTARY BUMP,

Specification of Letters Patent.

Application filed October 6, 1920. Serial No. 415,141.

To all whom it may concern: Be it known that l, GUSTAV Bl Persons, a citizen of the United States of Amerlca and a residentof Yonkers, in the county Westchester and State of New York, have invented a certain new and useful Improve ment in Rotary Pumps, of which the following is a true and exact description, reference being had to the accompanying drawings,

which form a part thereof.

My invention relates to rotary pumps or compressors of the type in which the rotating piston consists of an eccentric ring contacting with the walls of the pump cylinder and provided with an extension forming a partition between the admission and delivery ports of'the pump. The object of my invention is partly to provide such a pump with a sliding grid iron delivery valve having means by which it is opened when the pressure'on the delivery side of the pum proved extension forms a slide working in a swivel block.

The nature of my improvements will be .best understood as described in connection with the-drawings in which they aregillustrated and in which Figure 1 is a side elevation of my imp ump taken as'on the section line 11 of ig. 2. Y

Fig. 2 is afront elevation of the ump pagtly in section on the line 2-2 of ig., 1, an

Fig. 3 is a face view of thegrid iron valve and its attachments. I

A and A indicate two pump cyllnders formed in a single" casting and providedwith face plates A and A A indicates the cylindrical surface of the cylinders. B

is a bearingin the casing for the swivel block; Bf is the admission chamber and B the delivery chamber which chambers can be common to both of the fpair of pumps. C is a passageor chamber ing having a port'C' leading into it from located cylinderwhich is crossed by the contacting ormed 1n the cas-- the delivery side of the pump and a-port C leading from it into the delivery chamber. D is the driving shaft towhich are secured eccentrics l) which are surrounded by eccentriclring pistons E provided at their upper ends with slides F which, as shown,

Patented Mag 31, 31921.

have openings F formed in them leading municating through a port F with the admission side of the cylinder. This construction is preferred by me though, broadly speaking, my invention can be utilized with pumps having admission ports formed through the walls of the cylinder. N indicates the swivel block through which the slide F works and which has its bearing in the cylindrical bearings indicated at B. G is a valve casin or bushing fitting in the chamber C an I having extending across said. chamber agrid iron valve seat G. H is'a grid valve seated on the seat G and having, as shown, a valve stem H to which are secured a piston I and a plunger 1'. J is a dash pot cylinder in which the piston I works, this cylinder having restricted ports J and J leading from its opposite ends and communicating with each other through an adjusting block J.- K is a cylinder in which works the plunger I the end of this cylinder connecting through a pipe L with,

the delivery side of the cylinder. By preference I connect this pipe with the port L at a point in the surface A of the line with the piston at the same time that the piston comes in contact with the means, to be described for closing the valve.- The I .;from the admission chamber B and comcylinder K, however, canconnect with the pump cylinders at other points, for instance,

as shownin dotted lines, with the port G.

M is the pivot of the lever M and M M of which engages the grid valve, as shown, while the arm M of the lever extends through the port C and lies. in the path of the rotating piston so as to contact with it and close the valve. At the end of the compression cycle of the pump I have indicated in dotted lines the position to which this arm of the lever is nioved by the piston.

In operation air is admitted to the recelvmg side of the-pump cylinder and preferably I admit the air, as shown, through the slide F for thereasonthat in this way the pressure which is incident to aslide leading into a receiving chamber is avoided.

. will This feature of the construction illustrated is not specifically claimed in this case but is claimed in my co-pending application for Letters Patent filed October 6, 1920, Serial No. 415,145. It will be observed that the location of the port F in slide F is such that it is closed during the period when the rotating piston is passing from the completion of one cycle to the beginning of another and when some compressed air which has not passed the delivery valve would be free to mix with the air drawn in preparatory to the second cycle. This feature, also, I believe to be new with me and it is claimed-in my before mentioned co-pending application.

lft will be obvious that the valve H is held on its seat in closed position by the pressure of the fluid in the receiver and that as the piston E proceeds with its compressing cycle the pressure will build up on the under side of the valve and also, passing through the pipe L build up in the cylinder K which is so proportioned that when the pressures on both sides of the valve are substantially equal the pressure exerted on the plunger 1 be sufficient to shift the valve to open position.

that the pressure should be cut off from the L at a point which is crossed by the piston at the same time that the piston comes in ters Patent, is

contact with the lever for closing the valve. At this point the pistoncontacts with the arm M of the lever M, M and this further movement shifting this lever to the position shown in dotted lines and through the lever arm M shifts the grid valve to a closed position,

and the piston I attached to the valve rod serve to cushion the movements of the valve by oil in the cylinder flowing through the passages J and J and a plug J from one side to the other of the cylinder. Having now described my invention What li claim as new and desire to secure by Let- 1. In a' rotary pump having a cylinder a rotating eccentric ring piston and a slide extending from said piston through a swivel block and an admission port, a delivery passage inthe cylinder casing having a grid valve seat, a grid valvewnrking on said seat to open and close the delivery passagea lunger secured to the valve stem, a cylinder or said plunger connected to the pump'cylinder at or near the delivery port and means for closing the valve lying in the path of the pump piston and contacting with it at the end of its delivery cycle.

After the pump piston has sub- 'stantially completed its work it is desirable 'to open and close the delivery lfhe dash pot cylinder J 2. In a rotary pump having a cylinder a rotating eccentric ring piston and a slide extending from said piston through a swivel block and an admission port, a delivery pas.- sage in the cylinder casing having a grid valve seat, a grid valve working on said seat to open and close the delivery passage a plunger secured to the valve stem, a cylinder for said plunger connected to the pump cylinder at or near the delivery port, a dash pot cylinder and piston working in connection with the valve to cushion its movements and means for closing the valve lying in the path of the pump'piston and. contacting with it at the end of its delivery cycle.

3. In a rotary pump having av cylinder a rotating eccentric ring pistonand a slide extending from said piston through a swivel block and an admission port, formed throu h the slide, a delivery passage'in the cylin er casing having a grid valve seat, a grid valve working on said seat to open and close the delivery passage a plunger secured to the valve stem, a cylinder for said plunger con- 4 ,andcontacting with it at the end of its delivery cycle.

4:. ln a rotary pumpfhaving a cylinder a rotating eccentric ring piston and'a slide extending from said piston through a swivel block and an admission port, a delivery passage in the cylinder casing having a grid valve seat, a grid valve working on said seat passage, a plunger secured to the'valve stem, a cylinder for said plunger connected to the pump. cylinder at a point in the pump cylinder crossed by therotating piston at or about the time that the piston contacts with the valve closing means and means for closing the valve lying in the path of the pump piston and contacting with it at the end of its 1 casing having a grid valve seat, a grid slide valve working on said seat, means for moving the valve to open it operating at the end of the", compression cycle of the piston and meansIf r closing the valve lying in the path of the eccentric "ring piston and contactingwithit at the end of its delivery cycle.v

GUSTAV B. PETSCHE. 

